The latest award comes in a survey of 1,000 Scots commissioned by the low carbon infrastructure taskforce, which is working to develop new “green” infrastructure projects.

The Forth bridge gained 49 per cent of the vote while the Glenfinnan viaduct, used in the Harry Potter films, came second with 13 per cent. Other engineering projects that featured included the Glasgow subway and the Falkirk Wheel.

The taskforce has also published a report calling for new high speed rail and energy schemes to become the “engineering projects for the 21st century and beyond”.

Sara Thiam, chair of the taskforce and regional director of the Institution of Civil Engineers, said: “The Forth bridge continues to be an icon of civil engineering excellence and we’re delighted that it has captured the public’s imagination in this way.

Newspaper article on memorial to honour those killed in the building of the bridge.

“The bridge is a great example of how engineering expertise can be used to create infrastructure which stands the test of time and shapes the way we live well into the future.”

Dr Katherine Trebeck, taskforce member and global research and policy advisor at Oxfam, said: “Scotland can take the lead, not just in reducing our carbon emissions and environmental impact, but in developing and sharing the solutions that will help end fuel poverty, improve health and create jobs.

“It’s great to see that three-quarters of the people polled also said they wanted to see investment in low carbon projects for the future.

“We hope people across Scotland will now show their support for their favourite projects for the future, as identified in the taskforce’s long-list.”